title: Genetic heterogeneity among bovine leukemia viruses in Japan and their relationship to leukemogenicity.
abstract: Bovine leukemia virus (BLV) infection in cattle causes persistent lymphocytosis, and a few percent of infected animals develop lymphoid tumors, namely enzootic bovine leukosis (EBL). In this study, a 440-bp fragment of the env gene was amplified from 204 tumor samples collected from different regions of Japan and analyzed by restriction fragment length polymorphism (RFLP) to determine the association of BLV with EBL. Of the seven RFLP types defined, types I, II, and III were dominant and found in 12.7, 75.0, and 8.3% of tumor samples, respectively. Cattle harboring type III virus were significantly older than other animals at the time of diagnosis of EBL. Type III viruses were found in approximately 33% and 5.5% of Japanese Black and Holstein cattle, respectively, with EBL. These findings indicate that genetically distinct BLV was associated with EBL in Japan and that the genetic profile may influence the leukemogenicity of the virus.
authors.affiliation: Department of Microbiology and Immunology, Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido, 061-0293, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Inoue
authors.forename: Keiko
authors.initials: K
authors.lastname: Matsumura
authors.forename: Kohei
authors.initials: K
authors.lastname: Maekawa
authors.forename: Kenta
authors.initials: K
authors.lastname: Nagatsuka
authors.forename: Miwako
authors.initials: M
authors.lastname: Nobuta
authors.forename: Moe
authors.initials: M
authors.lastname: Hirata
authors.forename: Airi
authors.initials: A
authors.lastname: Minagawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Osawa
authors.forename: Katsunori
authors.initials: K
authors.lastname: Okazaki
mesh_terms: D000818:Animals; D002417:Cattle; D016583:Enzootic Bovine Leukosis / Q000821:virology*; D018740:Genetic Heterogeneity; D007564:Japan; D001909:Leukemia Virus, Bovine / Q000235:genetics* / Q000302:isolation & purification; D012150:Polymorphism, Restriction Fragment Length; D014759:Viral Envelope Proteins / Q000235:genetics
chemical_list: D014759:Viral Envelope Proteins